Channel Stuck?

That would be very hard to do considering that it is an auditeria and the cafe (or house) lights are controled by that dimmer rack as well. If we lock out then the cafateria will have no lights, and I'm quite sure that the administration won't be too fond of that. Is it safe enough to remove the module then turn the power back on with a missing module, lock the dimmer rack, then lock the booth?
Actually, it is not a good idea to run a rack with a module out. No because of electrical hazard as much as the fact that the large opening in the rack will suck in lots of dust and debris. However, I would not worry about that until you isolate the problem. First swap modules. Then report back to us. No matter what you determine the issue is, you will need to get in touch with your local dealer to get things fixed or replaced. They will be able to tell you how to deal with the problem, and they will probably even come out and help.
 
Seems like we determined the "local dealer" is over an hour away. So a "housecall" would be very expensive. It's probably better for you to take the dimmer to them... but first let's prove that it actually is the dimmer that is the problem by doing a swap. On the other hand it might just be a good idea to pay for the house call to have them take a look at the whole system. Given the years of neglect it's had. Make sure when you do the swap you have a working light on the dimmer channel that the questionable dimmer will be in control of.
 
Could I suggest that a wise investment for your next budget is to buy a spare dimmer module, this will save you from this problem next time and it will also save money long term, as you can just send off faulty dimmers for repair.
When you know how to do jobs like this it is easy, like most jobs, but we had to be cautious in advising what to do as electrocuting students causes very bad public relations issues.
 
Well guys, I know how much you all think it needs to be repaired by a pro, but all repairs are prabably going to have to be made by me, the sound tech, and the building manager due to limited budget ("limited budget" = $0.00). Like I stated (mabey in another thread) a lot of new things that we get are bought by me and the sound tech. So if it needs to be repaired I will probably be the one funding it.

I'm guessing that the fault (again if there is, I haven't tested it yet but I want to get everything figured out so that I can just go ahead with the repair if it proves to be the module) doesn't lie in the breaker itself because breakers are pretty simple and I really don't know of anything that can go wrong with them that could cause this particular problem. But there are recanguar black boxes in the module; one for each breaker. Im guessing that if the problem lies within the module it lies in that. Do you think it would be possible for me to get a new one from the manufacturer? Or is it a generic part that can be ordered from a different company?
 
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I believe that is the SSR. You will need the correct one, but judging by other posts a 6 year old could do it. No offense to 6 year olds..
 
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...But there are rectangular black boxes in the module; one for each breaker. I'm guessing that if the problem lies within the module it lies in that. Do you think it would be possible for me to get a new one from the manufacturer? Or is it a generic part that can be ordered from a different company?
Yes you could get a new one from the manufacturer; you can also probably buy the exact same part less expensively from another source. The most common brand is Crydom (Aromat is another), and the generic name is "PowerCube" or SSR (solid state relay).

See this thread.

I suspect you'll find the problem stays with the slot, and not the module, and thus indicates a control issue. When SSRs fail, they generally either won't turn on at all, or stay on forever. If it IS the SSR, they're around $35.00, unless purchased from the dimmer manufacturer (significantly more).
 
I'm going to add to my last post and say that it's probably not the SSR. From what I have read recently, SSR's usually fail pretty quickly and in either full on or full off. Also, you would probably notice a physical deformity when comparing it to other modules, such as melting or a bulge in the plastic from overheating.

I don't think circuit breakers can fail this way. If so you would have an arcing event which would probably lead to rapid failure in a rather catastrophic manner.

As others have said, swapping modules to see if the problem follows the module or not will tell you alot. I am personally beginning to think that it is a problem in the signal line or a possible failure or glitch in the control module. That would need to be assessed by someone who is well versed in electronics and diagnostics/DMX.

Working on the dimmer beyond replacing SSR's would also require solid knowledge in dimming equipment. They deal with much more power than most electronic equipment found in schools and can do an untold amount of damage if done incorrectly. It's a good idea to keep in mind that lives are depending on that dimmer pack not catching on fire after it's worked on. I'm not saying that because I don't have faith in you or your building manager's electronics repair skills, it's more of an insurance/assurance thing.

One final word, don't feel obligated to foot the bill out of your own personal finances.
 
Well guys, I know how much you all think it needs to be repaired by a pro, but all repairs are prabably going to have to be made by me, the sound tech, and the building manager due to limited budget ("limited budget" = $0.00). Like I stated (mabey in another thread) a lot of new things that we get are bought by me and the sound tech. So if it needs to be repaired I will probably be the one funding it.
One final word, don't feel obligated to foot the bill out of your own personal finances.
I have to echo what Lester said, and I think add a little more force. I know that you love what you do, and working as crew at your school, but you should NEVER invest your own money fixing the schools problems. The same goes for using your own personal gear for school functions. Yes, it sucks to have 0 budget, and it sucks to have gear that doesn't work, but it is NOT YOUR JOB nor your obligation to fix it from personal funds. If the theatre department wants to solicit donations from parents to get things fixed, that is one thing, but you set a very bad precedent if you fix/buy gear out of your own pocket, or if you allow personal equipment to be used by the school.

Why is it a bad thing? The school, the district, and the city should be taking care of the investments they make. If you go around fixing things out of your pocket, then the powers that be will never see the need to budget for proper maintenance, because things just magically work. It may seem like a lousy situation, but ask any of the CB members who are involved in academic theatre, and they will tell you the same thing.

If the school administration won't come up with the money to get the equipment fixed then you should get other people involved. By that I mean that you should talk to your parents and the parents of other theatre kids, have them complain that the theatre is not being properly maintained. Go to the superintendent if you have to. Just don't spend your own money.

If worst comes to worst and you can't get the money to get it fixed, don't use the bad dimmer. When someone from the administration asks why there isn't enough light, tell them it is because you need money to get the system fixed. You would be amazed how quickly things get done when the people with the money experience the issue firsthand.

I'll step off the soapbox now, I think we talked about this in another thread too. Just something to keep in mind.
 
I'd have to agree with Alex's last post. However, it's not like I haven't spent my own money, or used my own gear for school stuff.

I personally make a distinction on some of those aspects though:

Tools. It's easier for me to know I have my own tools, the right ones for the job, and easily at hand. I keep these tools in a locked bag, and in a locked room overnight, but they do live at school. People know that these are my tools, and I don't tend to lend them out, and if I do it's to people I know well and trust to respect my gear. So this is something for personal use (plus I love tools and stuff: I'm a geirdo.) Lastly, it's not like I'm leaving my tools behind. If I have work to do somewhere else, or eventually leave school, my tools come with me.

Certain organizations around campus are student driven. Things like coffee house and other events. In these situations I'm either personally invested in the project, or helping out a friend. I don't spend any money on anything for the Theatre Dept, unless I justify it to myself (For instance I pilfered 6-8 cuts of gel, and replaced it with a new sheet of R60).

I think fixing things and investing time isn't an issue, it's where money comes into play. Personally, I find it calming to go into the theatre, even during high-stress / multiple test times, and work on something. So in that respect stuff gets "magically" fixed.

You are also the one without a working lightboard, right? And you do have school assemblies in your building, right? Perfect! Don't worry about a work-around for your next assembly. When the Head Master takes the stage and has to spend 45 minutes talking in darkness, he'll feel pretty stupid, and you'll get something new pretty quick.
 
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Although I'm sure I'm skilled enough to replace an SSR/SCR, I have never done it. Why? Because I don't want the personal responsibility for what could happen if I did it wrong. When I've had them repaired in the past it's cost about $75. The extra money out of my budget is worth passing the responsibility on to a professional.

The school/district must have an electrician. If so order the part and instructions and have the electrician do the work.

As for if it is the SSR or not. Since cleaning out the rack didn't work, I'm voting with Derek that I bet you'll find the dimmer is not the problem. As has been said these things usually break and stay on or stay off. Ghosting is usually more of a control issue. My guess is a problem in either the dimmer control settings or in the console. But don't fear, we are working our way through the list of possible problems here one at a time and cleaning the rack and elimination a bad SSR are the best places to start.
 
charc I think you were a little hit or miss especially in reference to tools and stuff. Being that I work for Alex I feel pretty certain that I can say he's not telling you to survive solely on the tools supplied to you. I can say that cause every single electrician that works for him brings personal tools. This is an ease of work thing. PTC supplies everything I need to do my work, I prefer the ease of my own tools so I use them. The time when this becomes problematic is when the company willingly or not takes advantage of the situation. Say something like the table saw goes down and so I bring in mine (I wish I had one) so that we can get the job done. I wouldn't even do this, I'd make the company figure out a situation, but you could argue that is being loyal and I might by that. When it's definitely a problem is if the company put off fixing the table saw because they had one that worked. You can imagine the situation pretty easily, if someone in the front office sees a request for money for a new table saw (or to fix the old one) and they walk back there and there's one that works they will put it off or deny the request.
I guess to sum up the difference I'd rely on the "if it ain't broke don't fix it" cliche. If it's broke, it needs fixed, that's the company's responsibility. If it ain't broke but you can make it work better (better tools, more tools) then you might consider personal investment.
 
Ok, So I'm dying to find out who called Sync's building manager. I offered to do it but didn't get the message in time to call. When I apologized for not calling he said Well somebody called and explained the whole process. I've sent a pm to everyone who was active in the first part of the thread (Derek, Charc, Alex, Phil, Porkchop... I'm assuming David didn't make a call all the way from Oz) and none of them made the call. So that leaves Soundlight, JD, Steve Terry, Lester, and Tim Miller who either only posted once or didn't post until after the cleaning. Or did we have a lurker from out of the blue call? DVSDave?

I just wanted to say thanks for calling to whomever did.
 
I did not call. I did send him a PM with my personal cell number and said if they have any problem or feel as if they got in over their head to give me a call. So.... Have they gotten it fixed yet?
 
So i was stumbling the internet and found this, it's kinda a crappy image but it gives a good idea of what it takes for power to hurt you.
 

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If you have ever taken electronics classes you will learn that 50ma is hardly any power. 1000mA = 1A. So in a 20A circuit means that it will take around 20000mA before the circuit shuts off. Also to most dimmer systems you have anywhere from 400A to 1200A of three phase feeding the panel, in which means you have 3 separate legs of power each being between 400-1200A. Something you dont want to get across. Also be aware contrary to popular belief circuit breakers do not limit the amout of amperage that comes across them, they just shut off after their rated amperage is exceeded. So you can easily have 1200+ Amps traveling down the line. This also means your home! Even though your house has any where from a 125-200A main breaker that big transformer out on the pole or sitting on the ground is stepping down around 60-250+KVA 250-1040A. And the electric lines that run to that transformer is around 60-120KV (yes kilovolts) = 60000V-120000V.

Here is some really educational and interesting videos of electricity.
This first demonstation video, they are running this setup off of a regular 120/240V generator.
http://www.youtube.com/watch?v=2_4gsPe7BuM

http://www.youtube.com/watch?v=MAlyEMQxTN0
 
So I got back to school today. I just switched the modules around and the problem does infact reside in the module. The Building Manager is going to have an electrician come in and look at it but is there anything else that I can do or try to fix the problem sooner?
 
So I got back to school today. I just switched the modules around and the problem does infact reside in the module. The Building Manager is going to have an electrician come in and look at it but is there anything else that I can do or try to fix the problem sooner?

The answer is: yes.

I'd suggest talking to Derek, Gaff, Icewolf, Porkchop, or TimMiller though.

However, if an electrician is coming in, it doesn't really matter until then.
 
Also be aware contrary to popular belief circuit breakers do not limit the amout of amperage that comes across them, they just shut off after their rated amperage is exceeded.

Yes, a very good point. Most breakers have a max flash rating of 10,000 amps, and that is why! When you short even a 20 amp line, you briefly have the full output of the pole transformer flowing through your circuit with the only limiting factor being the resistance of the wire. If your are at the end of a long cable, it may not seam like a big deal, but that's because your cable briefly turned into a resistance heater limiting the power flow. We see bigger booms the closer we get to the mains because the thicker gauges have a lower resistance. In any case, there is no limiting done by the breaker, it only switches open after it's response time elapses. By the way, that response time can be all over the place! Some 20 amp breakers will pass a 25 amp flow for 20 minutes before they trip. The higher the current over the rating, the faster the breaker will trip...... Unless it jams! Although rare, it does happen and that can get ugly!
 
... but is there anything else that I can do or try to fix the problem sooner?
Actually, the answer is NO, except to put the module in a place where dimmer#1 on the module (which used to be 5, correct?) is in the least important place, a normally unused circuit perhaps? Then when the electrician comes, show him this thread, and explain what you've done, and suggest politely the replacement of the SSR. In the meantime, you could look at the SSR to see if there's a brand and model# on it so you can get an estimate of the price via the Internet. Like I said previously, these run $30-$50 generally. If replacing the SSR does not solve the problem, I'm afraid you'll have no choice but to contact Lehigh to see what they recommend.
 

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